Research Topics

Theoretical and applied studies in the area of control system theory. Particular interests are directed to the hierarchical system theory, which give ground to overcome the peculiarities between the complexity of the real technical systems and the requirements towards the quality of their design, implementation and management.

First priority system under consideration is the complex, wide distributed, and decentralized system, which take part in the computer and communication systems. Particular interests are supported towards the transportation system, where suits of practical problem are addressed: traffic flow, real time management, optimization, and design.

Optimization theory is widely applied in the studies in the department. Both off-line and on-line areas of applications are considered. Optimal structure, topological design, parameter estimation of networks (computers, communications, transports) are determined, modelled, estimates, assessed. The dynamical behaviour of such system is assessed, controlled and managed.

The applied researches of department concern analysis, modelling, design, implementation, management of distributed computers, communications and transportation services. Problems of optimal real-time, dynamical routing and fleet management are designed of solves. Appropriate fast algorithms for solution of problems and their implementation are derived. Internet and World Wide Web technologies (both hardware and software are applied). The studies in the department support both national and international scientific and technical programs and projects.

Most Important Achievements

New control strategy in complex hierarchical systems has been derived. It performs coordination between the control levels in a hierarchical system. The new control strategy, named "non iterative coordination" has been developed to overcome the delays, which take places in the information transfer between the hierarchical levels in the complex, distributed system. Applications for optimization of the information transfer in wireless communication and for optimal management of the transportation flows in urban network are implemented.

A set of models, concerning the traffic intensity in urban network and the corresponding noise level has been derived. These models allow optimizing the noise pollution in urban areas by controlling the duration of the green lights on the crossroad section. A real time algorithm for evaluation and implementation of the optimal solutions has been derived. Applications on the downtown of Sofia have been implementing.

Internet and Web technologies have been applied in technical and information distributed networks. Access to distributed database, with mirror component in Bulgaria, Romania and Greece has been performed. The communications towards the three nodes above are done through Internet. The system supports the freight transportation market on the Balkan corridor Romania-Bulgaria-Greece. The users, mainly customers from the transportation industry register goods and means of transportation in the systems. Thus electronic market is available and benefits are obtained concerning the transportation management, goods distribution and logistics services. The system is deployed according to the FRETRIS project partly, funded by the EC.

Distributed information system supporting electronic data interchange (EDI) and electronic commerce (EC) solutions is designed and applied in the practice of the port authorities on the Balkan area. Solutions for paperless business technologies secure transactions and optimizations of the maritime freight transportation area derived. Internet solution for EDIFACT standards and modern XML languages are applied. The system is partly funded by the EC, according to international project development.

Modelling, optimization, assessment and implementation of routing algorithms in distributed interconnected computers and communication systems are performed. Analytical relations between the traffic load and the network parameters are defined. Appropriate optimization problem is defined and corresponding real-time algorithm for solution is derived. Real time management protocols in networks are applied for solving the "bottle-neck" problems. Software tools for on-line monitoring of the network state and traffic intensity are marked out.

Client server technology is applied for solving problems of optimal routing of information flows; multiply access to a common communication media; database applications through the global network Internet.